Kids toy scale
Kids love to play the toy grocer's shop. Then they need a toy scale. It's a great game and a wonderful opportunity to gain experience in simple physics.
This scale is precise to a few grams over then the typical toys you get on the market. The pivot points are equipped with small ball bearing (ZZ685 5x11x5) and the arm constructed like a parallelogram keeps the 'bowls' straight.
Tomo Kihara created a derivate of this scale as a tool for 'Street Debater', an alternative to begging. Read more about his project here.